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This paper presents the semi-analytical solutions for a vertical load moving on an inclined simply supported beam. By adopting the energy approach along with the Fourier sine series for the beam deflection shape, the governing equation of motion is obtained as an easy-to-solve ordinary differential equation. The frequencies of the inclined beam excited by the moving load can be expressed in analytical form which elucidates the intrinsic and fundamental features of the solution. The moving load problems solved herein show that the dynamic responses (deflections) at any point on the inclined beam with respect to the moving load position are smaller with increasing angle of inclination. For more insights into the axial load effect on the beam stiffness, the exciting frequencies are found to decrease as the load moves up the inclined beam. Interestingly, while the moving load is traversing over a certain portion of the beam, the frequencies stay constant rather than decrease monotonically; in other word, the stiffness of the inclined beam remains virtually unaffected when the moving load passes in this portion of the inclined beam. The stability issues of the inclined beam with a moving load are discussed by examining the determinant of the global stiffness matrix of the beam. Moreover, the maximum magnitude of moving load with allowable deflection is obtained to provide design recommendations.

International audience; Relaxation of internal friction of Zr57Nb5Al10Cu15.4Ni12.6 metallic glass was investigated by mechanical spectroscopy. The stress relaxation of internal friction with different aging temperature was described by Kohlrausch-Williams-Watts (KWW) equation. The shear viscosity behavior during linear heating can be interpreted as a result of the local irreversible structural relaxation with distributed activation energies. The results show that the dynamic heterogeneity and the atomic mobility are stimulated by the increasing annealing temperature.

An extended multiscale finite element method is developed to solve the mechanical behaviors of heterogeneous materials with randomly distributed polygonal microstructure. A type of rational oversampling technique is imposed to calculate the oscillatory boundary conditions for the construction of multiscale base functions. To improve the accuracy of the method, a mixed extended multiscale finite element method, which combines the extended multiscale finite elements method and the traditional finite element method into a same model, is developed. In the method, the regions with multiscale features are modeled by the multiscale coarse-grid, while the region without multiscale features or the domains that need a high-precision computation are directly meshed by the general finite elements. Two applications of the multiscale methods on heterogeneous wood structure and the closed liquid cell materials are presented in numerical examples. The results indicate that the multiscale methods developed in this paper have high accuracy and efficiency.

The small outline transistor (SOT) devices which were interconnected with 20 μm copper bonding wire and encapsulated with commercial epoxy molding compound (EMC) have been used in a series of reliability tests which including the thermal shock test, the electrical service life test, and the isothermal aging test. Isolated IMC spots were found at the bonding interface during the thermal shock test. No void or crack was observed even after 1500 cycles thermal shock test. No electrical failure was happened. The isolated IMC spots also occurred at the Cu/Al bonds interface after 500 h electrical operation. After 1000 h electrical operation, the sizes of the IMC spots were about 0.5 μm. No layered IMC was observed. The IMCs were formed at the bonding interface when the aging temperature was between 150 °C and 250 °C. Micro cracks and Kirkendall voids were observed with the aging time of 9 days at 200 °C and the aging time of 9 h at 250 °C. The minor element in the EMC, Sb, has reacted with Cu wire and Cu bond surface at 250 °C when the aging time was more than 16 h. Cu3Sb was the main product of the diffusion reaction. With the aging time of more than 49 h, the Cu wire was crashed into pieces and the Cu bond periphery has been severely corroded.

The electrical resistivity, thermal conductivity and low-frequency internal friction of Cr 75 (Fe x Mn 1− x ) 25 ( x =0.64, 0.72) alloys are studied in the temperature range 77–300 K. The initial increase in the resistivity and the decrease in the thermal conductivity as temperature decreases below T N are attributed to the progressive opening of the energy gap related to the antiferromagnetic transition in the alloys. The energy gap is estimated and the lower limit of value 2Δ( T C )/ k B T C is 1.13 and 1.30 for Cr 75 (Fe x Mn 1− x ) 25 of x =0.64 and 0.72, respectively.

A new formalism to calculate extended X-ray absorption fine structure (EXAFS) for slightly anharmonic vibrational system has been developed. From the formalism, we derived the close relations among local thermal expansion, effective pair potential, cumulants and pair distribution parameters.

The photodissociation of jet‐cooled HgI2 has been studied in the 244–323 nm region using a tunable ultraviolet (UV) laser. Dispersed emission, action, and multiphoton ionization spectra have been recorded. A vibrational analysis of the action spectra near 305 nm shows that the production of excited Hg atoms from HgI2 UV photodissociation proceeds through a HgI ground‐state intermediate. Near 248 nm the results are less conclusive. Possible reasons for a wavelength‐dependent kinetic mechanism are discussed.

The emission spectrum of ZrCl produced in a corona-excited supersonic jet discharge is presented. The C system near 410 nm is assigned to a 4Π—4Σ transition. The vibrational structure within each multiplet sub-band is ascribed to Δν=0 sequence bands. A small number of Δν=−1 sequence bands have allowed estimates for the ground and excited state vibrational frequencies to be made for the first time.

A new high resolution photoelectron spectrometer designed for core level photoelectron studies of gas phase volatile and involatile compounds using synchrotron radiation is briefly described. Xenon NOO Auger spectral linewidths of 0.13 eV indicate that the electron resolution is 4 and ligand field splitting of the Xe 4d core level of XeF 2 .

The present study aimed to assess location and relative amounts of transforming growth factor alpha (TGFalpha) and its receptor (EGFR) in ovine oocytes and preimplantation embryos by using immunohistochemical technique that was graded on a relative scale of 0-3, with 0 representing absence of staining, and 3 exhibiting prominent staining, and to evaluate the effects of TGFalpha/EGF on in vitro development of preimplantation embryos by adding different concentrations of EGF and TGFalpha to culture medium. The results showed that EGFR was abundant in cell plasma membranes in immature and mature oocytes, cumulus cells of immature cumulus-oocyte complexes (COC), fertilized oocytes and at different stages of embryo development. However, the relative amounts in inner cell mass (ICM) (1+) was less than that in trophectoderm (TE) cells (2+) at the blastocysts stage. The staining pattern for TGFalpha was a similar to EGFR. However, the staining for TGFalpha slightly increased in the fertilized oocytes (1-2+) as compared to immature and mature oocytes (1+). TGFalpha was mainly detected in the cytoplasm close to the membrane in both ICM and trophectoderm (TE) cells. The developmental rate of 8-cell stage embryos cultured with 5 ng/ml TGFalpha was increased as compared to other treatments (P0.05). There was no significant difference in the rate of development of blastocysts cultured with 5 ng/ml TGFalpha, 20 ng/ml EGF, 20 ng/ml EGF+5 ng/ml TGFalpha or the control treatment (P0.05). In addition, there was no significant difference in the number of cells in blastocyst stage as compared with different treatments (P0.05). However, TGFalpha alone enhanced cell survival rated (P0.01) and reduced apoptosis. We concluded that TGFalpha can improve development of ovine preimplantation embryos at the 8-cell and blastocyst stages in vitro.